Answer:
10%
Step-by-step explanation:
20%=20/100=0.20
75$x.0.20=15$
The price when she received a 20% discount was:
75$-15$=60$
Then, the web site applied a 10% service fee to the discounted price, so you have:
10/100=0.10
75$x0.10=7.5$
60$+7.5$=67.5$
So, if 75$ is the 100% of the price, what percentage represents 67.5$?
75$--------100%
67.5$------x
x=67.5 x 100/75
x=90%
Then,
100%-90%=10%
B=75, not 27
Sorry, I had to use a napkin because I was too lazy to get a paper....let me know if u need me to explain anything
A^2 - b^2 = (a-b)(a+b)
To test it, expand the right hand side.